Coupler
RailCar Couplers, AlsoKnownAs Couplings are mechanical devices that join railcars so to makeup an entire train. Coupler type, track gage, brakes, clearances,... are just some of many factors that determine compatibility with other rollingstock & a specific railway. Coupler assemblies typically include the knuckle, head, shank, release, striker, yoke, follower, drawgear,... : Coupler designs generally fall into 1 of these 3 categories: * FullManual Couplers require a trainman to step between cars to manually couple+decouple mech +pneu +elec connections. * SemiAuto Couplers automaticly couple+decouple the mech connection, but require manual pneu +elec connections. * FullAuto Couplers automaticly couple+decouple all mech +pneu +elec connections. : : Janney\AAR Couplers : Janney\AAR couplers, AlsoKnownAs APT\ARA\MCB\Knuckle\Nuck couplers, are a SemiAuto design; mechanical coupling+decoupling is automatic; any required PneumaticPipe+ElectricCable connection is seperate+manual. Inspired by the human hand, then patented 1873~1914 by E.Janney Of USVI, the design was steadily improved thru several decades by the McConway&TorleyCo, PennsylvaniaRailRoad\PRR, MasterCarBuilders\MCB, AmericanRailwayAssoc\ARA, AmericanAssocRailways\AAR & AmericanPublicTransportion\APT to become a practical reliable coupler, requiring little maintenance, durable in abusive service & extreme environments. : AAR couplers are simular to Willison couplers, but with hinged Nucks instead of locking Heads. At least one nuck must be open for mating; as cars come together, the Nucks are pushed closed by the opposing palm until LatchPins engage. To decouple, cars are pushed together for slack, one pin raised via a SideLever, that nuck opens & the cars are free to part. An advantage over Willisons, AAR Nucks are weaker than the Head\Shank, acting as ShearPins if overstressed & are readily replaced by crew; a disadvantage is Willison couplers mate without concern for Nuck closed\open position. : AARC\MCB5\Transition couplers were mandated 1893 by the US Congress to force replacement of dangerous Link&Pin & unreliable MillerHookPlatform couplers, reduce injury & allow interchange across 4f708 1m435 Gage NorthAmerican railways. These couplers have MCB5 Contour, 9i250 LongHeads (measured from MatingLine to Horn), 9i000 TallNucks, mate to all AAR\APT\ARA\MCB subtypes & old L&P+MHP couplers via SplitNucks. Upto 21i TallNucks were used on rough\uneven track. : NationalCo.Sharon (make.model) couplers were likely the most popular choice by lokomotive & wagon builders\owners\operators from the multitude of 1893~1914 AARC\MCB5 designs; many Sharon couplers remain in use on Preserved\Museum stock as of this 2019 writing. These couplers have MCB5 Contour, 9i250 LongHeads (measured from MatingLine to Horn), 9i000 TallNucks, mate to all AAR\APT\ARA\MCB subtypes. : AARC\L&HD\DropHead couplers (make.model=BECo.DropHead) are a hybrid design first conceived ~1898 by N.Gresley of Britain & produced at BuckEyeCo\USOh, for TeakCorridorCoaches. They've since been produced in the UK\EU for use on CorridorSteamTenders, Mark1+2+3 Coaches+MultiUnits & Class59+89 Lokomotives. These couplers have MCB5 Contour, 9i250 LongHeads, 9i000 TallNucks, mate to all AAR\APT\ARA\MCB subtypes & pivot downward to reveal a L&H coupler hook. : AARD\ASF3\Alliance couplers (make.model=ASF.Model3\Alliance) were first designed ~1913 by R.Janney (son of E.Janney) & manufactured by AmericanSteelFoundries at USOh Alliance, in heated competition for the pending 1915 ARAD standard, but lost out to A.Bazeley+NaCo. R.Janney+ASF then defiantly marketed their Alliance outside of NAmerica as a LessCostly LiteDuty coupler. These couplers have ARA10~Improved Contour, though shorter\weaker 10i00 LongHeads compared to AAR\ARA standard 12i00 LongHeads, but remain compatible & mate to all AAR\APT\ARA\MCB subtypes. As various steel foundries around the world (LAFHenricot, OMBES, Sable, TedRail, WCR, BradKen, RIS...) licensed +marketed +improved the design, AARD\ASF3\Alliance couplers & several resulting evolutions became common on Passenger +Freight stock of Australia +Brazil +Britain +Burma +China +Cuba +Dijaboti +Ecuador +Ethiopia +India +Indonesia +Japan +Korea +Malaysia +NewZ +Panama +Phillipines +Saudi +SAfrica +Taiwan +Tanzania +Thai +Vietnam +Zambia +Zimbabwe... : AARD\ARAD\Bazeley couplers (make.model=NaCo.Bazeley), superceding AARC, became the AARD\ARAD standard in 1915 for both Freight & Passenger duty. These couplers have ARA10~Improved Contour, stronger 12i00 LongHeads, 9i000 TallNucks & mate to all AAR\APT\ARA\MCB subtypes; optional 11i00 TallNucks were often used on Lokomotives. : AARE\ARAE\GeneralDuty couplers, superceding AARD +AARC, became the AARE\ARAE standard in 1932 for Routine Freight: BoxCars +CenterBeams +Hoppers +Flats +Gondolas +InterModals +AutoRacks +Reefers... These couplers have ARA10A~Improved Contour, 12i00 LongHeads, stronger 11i00 TallNucks & mate to all AAR\APT\ARA\MCB subtypes They are the most common of AAR\APT\ARA\MCB couplers. : AARF\APTF\InterLock couplers, conceived in 1901 by E.Ramsay@PrattCoalCo of USAL, became the AARF standard in 1954 for HazmatTank+RotaryGondola Freight Wagons & later the APTF standard for DualService=Freight+Passenger Lokomotives. These couplers have AAR10A~SlackReduced Contour, 12i00 LongHeads, 11i00 TallNucks & mate to all AAR\APT\ARA\MCB subtypes. They prevent decoupling\punctures in derailments, minimize slack, & allow RotaryDumping of Gondola Freight Wagons. : AARH\APTH\TightLock couplers evolved from the 1908 VanDorn#20 on the Hudson&Manhattan, the 1909 VanDorn#31 on the Chicago&Southern & the 1915~1927 HType by E.Henricot of Etienne Belgiumused on NMBS\SNCB stock, which were efforts to improve upon MCB5+ARAD+Alliance couplers of that era. A further improved & noticably evolved design, first used 1928 in NAmerica on the NewYorkCentralRR, became the AARH\APTH standard in 1947 for Passenger Lokomotives+Wagons+MultiUnits. These couplers have AAR10A~SlackReduced Contour, 12i00 LongHeads, 11i00 TallNucks & mate to all AAR\APT\ARA\MCB subtypes. They prevent decoupling\telescoping in derailments, minimize slack, & allow Pneumatic+Electric appliances that convert AARH couplers from SemiAuto to FullAuto operation. : AARD\L&HS\SwingHead couplers, which pivot to a Brit\Euro\L&H coupler hook, are used on unitized Passenger +Goods\Freight stock of Britain +SriLanka. : AARE\L&HI\SwingLink\CentreBuffer couplers, with pivoting Brit\Euro\L&H coupler links, are used on unitized Passenger +Goods\Freight stock of India +SriLanka. : : Link&Hook\L&H Couplers Link&Hook couplers, AlsoKnownAs British\English\Euro\UnionInternationalChemin=UIC, are the defacto standard coupler for trains of Britain +IreLand +Europe +Israel +NorthAfrica... These couplers originated on the railways of Britain & Europe, developing\evolving from ~1804 thru today. Several compatible subtypes are described below. L&H3\ThreeLink couplers are a FullManual design, AlsoKnownAs Loose couplers. Being the earliest Link&Hook subtype, these couplers were phased out 1968~1980 as LooseCoupled BritishRailways\BR Goods\Freight stock was retired. ThreeLink couplers are cheap to make & functionally simple, yet dangerous to use. Stock fitted with this coupler have a drawhook connecting to basic draftgear, along with a pair of sprung buffers on each end of the car. A ThreeLink chain hangs from a Gedge\Notch in each hook shank; after 2 cars are pushed together, one of the ThreeLink chains is lifted into the opposing hook. A shunting pole can be used to manipulate the chains, which is somewhat safer than being between the buffers. A disadvantage of this design is the resulting "LooseCoupling", meaning several inches of slack is inherent & must be taken up in tension as the consist accelerates & again compressed as the consist decelerates. This causes significant wear on car structures, draftgear, buffers & lading, thus as improved coupler designs became available, only slow Goods\Freight stock were allowed to use ThreeLink couplers. An advantage is less of the consists weight is on the locomotive as it accelerates, thus why this coupler remained is use so long. : L&HC\CloseLink couplers are a FullManual design, AlsoKnownAs Instanter couplers, & mechanical improvement over ThreeLink couplers; the center link is now replaced with a special triangular link, allowing 2 positions: LooseCoupled for shunting or CloseCoupled for mainline running. A shunting pole may be used to Connect\Disconnect\Adjust the links. : L&HF\L&HP\ScrewLink couplers are a FullManual design, typical in Britain +IreLand +Europe for both Goods\Freight & Passenger stock. The ScrewLink design is a mechanical improvement over both ThreeLink & CloseLink couplers; in essence it is a ThreeLink with an OpposingThread TurnBuckle replacing the center link; however it is more dangerous as shunting poles can not be used & trainmen must go between cars +buffers for both coupling & decoupling. : : Link&Pin\L&P Couplers Link&Pin\L&P couplers are a FullManual design that originated on NorthAmerican railways in the early 1800s. They are cheap to make, functionally simple, yet dangerous to use: a drawbar\buffer projecting away from the railcar frame allows access to a vertical pin that holds a link in place; the link extends out the end of the drawbar\buffer; as cars come together, the opposite pin is raised by one hand of the trainman while his other hand guides the link into the opposing drawbar\buffer, then the pin is lowered thru the common link, thus coupling the cars. Decoupling is the reverse procedure & only slightly less dangerous for a trainman. : As NorthAmerican railways expanded & became more interconnected, L&P couplers became more problematic: injury & death to trainmen due to these couplers became common as RailCars became heavier; loose Pins & Links often were missing or the wrong size. Finally in 1893 the US Congress mandated a 10+Year transition, outlawing the L&P along with other lesser coupler types of that era, & required newly developed Janney couplers (per MasterCarBuilder\MCB standards) for NorthAmerican 4f708 1m435 Gage interchange. In the years since, L&P couplers have been generally outlawed worldwide, now only seen on Preserved\Museum stock & isolated Colonial\Industry\Mine\Plantation stock. : : Scharfenberg Couplers Scharfenbergs are FullAuto couplers, first designed 1903 by K.Scharfenberg of Konigsberg Germany. AlsoKnownAs SchaKu\Dellner\Voith couplers, the Scharfenberg has become most common worldwide on PassengerUnit trains: DMUs +EMUs +Tram\LRVs... As two Scharfenberg couplers come together, brakepipes mate & cocks automaticly open, & rotating covers reveal electric contacts. To uncouple, a remote release is operated from the cab. Evolutions of the Scharfenberg, Shibata & Shinkansen couplers are standard on Japanese +Korean passenger stock. Relative higher cost\complexity, need for covers\heaters in dirty\winter service, & limited draft ratings, cause this coupler to be rarely used on freight\goods stock. : : Willison\CAK Couplers Willison\CAK couplers are a SemiAuto design originally patented 1913 by J.Willison@NationalCastingsCo\NaCo of USOh. First intended for abusive industrial environments, the rugid Willison coupler has become a world standard for Farm\Plantation +Mine\Industrial +Colonial\NarrowGage railways, & are available in 050% +075% +Full sizes. Willison Couplers operate much like Janney Couplers, though with interlocking Heads instead of hinged Nucks. A Willison advantage compared to Janneys, is they mate without concern for Nuck closed\open position; a disadvantage is Willisons do not have breakaway Nucks & a broken Head\Shank is not easily repaired by TrainMen. : After the original design was enlarged\improved by NaCo Of USOh & LAF Of France, hybrid CAK+L&H Couplers were used on 1932~1970 French\SNCF.141TC Passenger lokomotives & coaches serving Paris~Nord routes. After further testing\improvement, in 1935 Russia made the Willison\CAK3 coupler standard for the entire RZD broadgage railway; this version has cast letters CA~3 meaning CоветскихAвтоKuppler3 in Russian or SA~3 meaning SovietAutoCoupler3 in English, & is used across continental Russia +FinLand +Mongolia +Ukraine +Turkey +Iran... A newer CоветскихAвтоKuppling5\CAK5\CAKv version is used in Russ~Euro interchange, being compatible with both Willison\Russ\RZD\CAK & Brit\Euro\L&H couplers. : : Refs * RailCarCouplers At OBTS Wiki * RailCarCouplers At WikiVisually : : Category:Locomotive Parts Category:Steam Locomotive Principles Category:Diesel Locomotive Principles Category:Electric Train Principles Category:Encyclopedic articles